1. Field of the Invention
The present invention relates to a cassette loading device of a tape recorder, and more particularly to a cassette loading device including a cassette holder and a conveyance mechanism for the cassette holder.
2. Prior Art
In the tape recorder market, specially so-called tape deck market, widespread are component types wherein a cassette is loading in a generally vertical direction to a front face panel of a cassette deck (in a direction generally parallel to the front face panel of the cassette deck), and is placed with its capstan side down so that letter on a label attached to the cassette on its face stand right for ease of reading.
Most of the conventional cassette decks employ a cassette holder as a means for cassette loading in which this cassette holder moves through a circular arc upon cassette loading.
FIG. 1 is a sectional view showing a conventional moving mechanism for a cassette holder to effect movement of the cassette deck through a circular arc, in which a cassette 1 is received in a cassette holder 2 which is rotatable about a shaft 3 between a cassette loaded position (shown by the solid line) and a cassette unloaded position (shown by two dots-chain line). With this arrangement, a capstan hole 4 of a cassette moves through a circular arc until it receives a capstan 5 when loaded, however, although the capstan hole 4 must measure 4.5 mm in diameter according to a standard, the diameter of the capstan 5 may take any value ranging from 2 mm to 3 mm and besides there is the trend to employ a capstan with a large diameter to hold extremely close tolerances upon finish of a product by grinding, holding surface vibration of the capstan at extremely low level, the capstan with a diameter not smaller than 2.5 mm being widespread in use at present. In such a cassette deck provided with a capstan having a diameter of 2.5 mm, for example, a radius R of a circular arc along which the capstan hole 4 moves must be 30 mm at the minimum for a practical use, and if the radius R is smaller than this value, the capstan hole 4 contacts with the capstan 5 or in a worse case the cassette 1 abuts the leading edge of the capstan 5, thus making it impossible to effect cassette loading operation. The present trend demands component type cassette decks having a shorter height, for example, one having a front face panel with 100 mm in height, in this case it is hardly possible to assure the minimum radius as mentioned above.